Many vehicles today have electric power steering (EPS) systems. EPS systems typically use an electric motor to provide a steering assist to a driver of the vehicle in manipulating the steering assembly and wheel, thereby reducing effort by the driver in steering the vehicle. During operation, vibrations within the vehicle may propagate to the driver at the steering wheel. For example, smooth road shake (SRS) is a type of vibration leading to driver complaints.
SRS is caused by internal periodic excitation such as wheel imbalances, tire irregularities, brake rotor imbalance and lack of precision piloting of the rotating members. Some EPS systems may employ active control mechanisms to mitigate SRS. Although conventional EPS systems may succeed in mitigating SRS, these control devices and methods may impact the driver's perception of steering responsiveness. For example, conventional control devices may adversely impact driver perception with respect to on-center steering and/or road feel.
Accordingly, it is desirable to provide improved EPS systems to reduce the steering wheel vibration of the vehicles while maintaining other desirable driving characteristics. Furthermore, other desirable features and characteristics of the present invention will be apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.